Answer: The measurements of the angles are: 110° ; 50° ; 20° .<span> _________________________________________________________ Explanation: ________________________________________________________ Note: There are 3 (three) angles in any triangle (by definition).
By definition, all the angles in any triangle add up to 180</span>° .<span> ________________________________________________________ The problems asks us to find the measure of EACH angle of the triangle.
We can set up an equation; given the information in the problem; to solve for the measure of EACH of the 3 (THREE) angles in the triangle: ________________________________________________________ </span>→ " <span>x + (x + 90) + (x + 30) = 180 " ; _____________________________________________ in which: "x" is the measure of one of the angles; (specifically, the smallest angle) in the triangle; "(x + 90)" is the measure of another one of the angles in the triangle; </span>"(x + 30)" is the measure of another one of the angles in the triangle; <span> ___________________________________________________________ By solving for "x" in the equation; we can solve for the measures of all the angles in the triangle; _________________________________________________ </span> → x + (x + 90) + (x + 30) = 180 ; <span> x + x + 90 + x + 30 = 180 ;
</span>→<span> 3x + 120 = 180 ; ______________________________________ Subtract "120" from each side of the equation ;
3x + 120 </span>− 120 = 180 <span>− 120 ; </span><span> to get: 3x = 60 ; ________________________________ Now, divide EACH SIDE of the equation by "3" ; to isolate "x" on one side of the <span>equation ; and</span> to solve for "x" ;
3x = 60 ;
3x / 3 = 60 / 3 ;
x = 20 ; _________________________________________ Now, we have the original equation: __________________________________ </span>x + (x + 90) + (x + 30) = 180 ; <span> in which: x = 20</span>° {the smallest angle) ; "(x + 90)" = "(20 + 90) = 110° ; "(x + 30)" = "(20 + 30)" = 50° ; <span>__________________________________________________________ Answer: The measurements of the angles are:110</span>° ; 50° ; 20° . <span>__________________________________________________________ To check our work: